This is a hot dry area south of the Arizona desert and inability to control the dust generated in order to comply with environmental requirements has been a constraint on achieving production increase objectives, with Government authorities threatening fines and the shutting down of the mine unless compliance can be achieved.

The dust can be seen from many miles away and blows over 60km into the USA where it is the source of many complaints.

A fleet of 3 Caterpillar 797 and two other similar sized trucks have been converted into water tankers in order to try to control dust generation.

These water trucks run 24 /7 and spray each section of haulage road every 2 hours but still fail to achieve satisfactory dust control.

In October 2013, which is an autumn month and therefore less hot and dry than summer, an average of about 8 million liters of water per day were used in dust alleviation efforts. Despite this satisfactory dust control was not achieved.

Existing dust management protocol was to apply 1l/m2 to haulage roads every 2 hours. Because of the nature of the soil, applying any more than 1/m2 would result in slippery roads and loss of traction for the haulage trucks which was particularly problematic on inclined roads and bends.

DustSuppresSOR, a new generation dust control product was applied to the haulage roads. While establishing the optimum application rate, up to 4l/m2 was applied without any slipperiness. In fact drivers reported improved traction on inclines and bends. Once the “loading dose” of DustSuppresSOR had been applied, dust suppression was maintained by applying just 2l/m2 twice per day (ie once every 12 hours). At this application rate water consumption was reduced by 60%

Because of the high plasticity of the soil, water applied for dust suppression has always created problems of slipperiness of the haulage road surface.

No such problems were experienced with DustSuppresSOR, even on steep inclines, even though application rates per application were higher.

12 hours after application of DustSuppresSOR.

Historically, even when the road surface was wet, dust was still blown up from the piles of earth and embankments on the side of the road by the passing trucks. Dust blown from windrow on side of road No dust from road

Application of DustSuppresSOR to these embankments once every 24 hours eliminated this problem. No dust blown from windrow on side of road

Solution Overview Water consumption reduced by 60% - from 8m liters daily to 3.2m liters daily DustSuppresSOR applied twice daily 3 water trucks can be parked and operating costs saved Dust is under control for the first time